Journal of Transportation Systems Engineering and Information Technology

Technology Policy of Rail Transit

ZHANG Guo-Wu

2011, 11(2): 1-11.

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The 22th conference of “Traffic and Transportation 7+1 Forum” sets its theme as “technology policy of rail transit”. The forum puts forward the function of different types of rail transit for urban rail transit, intercity rail transit and high speed railway, with national and regional socio-economic development demands. The statistical indicators of per unit turnover energy consumption are studied in different rail transit system, and its model and method are introduced. According to the actual statistics and the simulation of train operation, trends in rail transit energy consumption are quantitatively calculated under different technology parameters and transportation organization plans, and proposes the technology policy of rail transit development in China from the perspectives of energy.

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Energy Consumption of Aircrafts in China’s Civil Aviation During 1960-2009

HE Ji-Cheng

2011, 11(2): 12-16.

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The energy consumptions of aircrafts during 1960-2009 are calculated, and the energy consumption intensity and its dynamic characteristics are analyzed, based on annual statistical data collected by Chinese Civil Aviation Statistic Center. The results show that the energy consumption of aircrafts in China increases at a rate of 0.4024 Mt standard coal equivalent per year. The energy consumption intensity of aircrafts decreases from 1.42 kg standard coal equivalent (converted t km) -1in 1960 to 0.46 kg standard coal equivalent (converted t km)-1 in 2009 at an average rate of 19.6 g standard coal equivalent (converted t km)-1 per year. The energy consumption of aircrafts exceed that of locomotives since 2002. The proportion of aircrafts energy consumption to that of vehicles in China is 4.4%. This study can provide some valuable data on the status quo of energy consumption of civil aviation of China. Furthermore, the estimation presented in this paper can also give some suggestions for making energy saving strategy in China civil aviation.

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Contribution Rate of Highway Passenger Transportation Price to Consumer Price Index

SUI Li-Na, CHEN Jian-Hua, CAO Mo

2011, 11(2): 17-20.

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Due to the alternate inflation and deflation pressure caused by the fluctuation of consumer price index, it has imposed more difficulty in the control of macro economy. Highway passenger transportation price is one of the basic indexes in determining the consumer price index, and in this article the contribution of highway passenger transportation price to the consumer price index is analyzed quantitatively by building a contribution degree model. The analysis shows that traffic index contributes a lot to the consumer price index and increases gradually, from 4.44% in 2002 to 7.47% in 2007, consistent with the trend of increasing private car possession; while long distance bus price index contributes less and keeps a stable level of 2.41% or so thus playing an important role in maintaining the consumer price index.

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Formation Mechanism and Cooperation Games of Logistics Alliance

XU Yang, SHEN Jin-Sheng, WANG Chuan-Tao

2011, 11(2): 21-26.

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In recent years, the rapid development of information technology, electronic commerce and economy has brought about the logistics pattern huge transformation, and the theory of logistics alliance arose at the moment. This paper analyzes the formation mechanism of logistics alliance from the perspectives of economics and systematology. The risk attitude is introduced into the cooperation games, and the influences of enterprise risk aversion, alliance synergy effect and various cost coefficients on the enterprise input and alliance cooperation are studied. The research results indicate that logistics enterprise’s willing to cooperate is been impacted greatly by both the self-logistics cost coefficient and the cooperation cost coefficient. In addition, enterprise with lower operating costs and a lower sense of risk aversion is more collaborative. In order to stimulate the enthusiasm of cooperation, appropriate encouragement and profit sharing is necessary, therefore, logistics alliance should develop appropriate access system and appropriate reward system depend on the actual situation. And then we illustrate our findings by a numerical example.

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Traffic Guidance Oriented Model of Traffic State Probability Forecast

DOU Hui-Li, WANG Guo-Hua, GUO Min

2011, 11(2): 27-32.

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In order to obtain the accurate and objective traffic state information to meet the demand of traffic guidance, and in view of the stochastic property and complexity of the traffic flow evolution on the urban road and the uncertainty of traffic state discrimination, an algorithm of Logistic regression for traffic state probability forecast is put forward based on the analysis of the mapping relationships between traffic state and traffic flow parameters. The proposed algorithm explores the function relationships of traffic state and the influencing factors by means of Logistic regression and thus gives the probability prediction of the traffic state of the next time period. Finally, according to the proposed algorithm, the grading traffic state probability forecast tests of different time periods is carried out using the field traffic flow data. The results of independent sample test indicate that the model has a finer precision and stability.

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A Safety Distance Design Model Based on Just Noticeable Difference

SHI Wei, WEI Yan-Fang, LI Xing-Li

2011, 11(2): 33-38.

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According to the theories of traffic dynamics, traffic psychology and psychophysics, the process that drivers perceive leading car’s movement through the distance changes between vehicles is explored, where just noticeable difference is introduced. The extreme cases for car-following behaviors are discussed and the range of the car-following distance and the relationship between the car-following distance and three factors, including the roughness of road surface, the velocity of vehicles and the reaction time of drivers are derived, respectively. Finally, regarding the lower limit of the range of the car-following distance as governing equation for safety distance, we have obtained the optimal values of safety distance under different road conditions, such as roads with anti-skid surface, asphalts pavement, rain, snow and ice. Compared with the safety distance in "the Road Traffic Safe Law", the rationality of this safety distance design is validated. These conclusions can provide a theoretical basis for the design of traffic safety and management.

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Game Theory Analysis on Service Mode of LogisticsInformation

WEI Zhen-Lin, ZHANG Yan

2011, 11(2): 39-43.

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The essence of logistics information is aimed at improving logistics efficiency, service standard, and saving the logistics cost, so as to enhance the enterprise core competence. In the practice of logistics information, although logistics information system as the carrier of logistics information is variable in terms of the difference of logistics information and enterprise business, the specialization and comprehensiveness have no doubt to be the direction in the decision of logistics information. The paper establishes the game model on the enterprise implementing the logistics information service which is based on the profit-oriented marketing system, and in the theoretical angle analyzes the terminal condition and detecting trend for enterprise carrying out the specialized and comprehensive logistics information service, tries to provide theoretical guidance and support for logistics enterprise making the decision of information and the government pushing logistics information.

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Path Planning and Control Algorithm for Intelligent Vehicles under Semi-Structured Road Condition

LIANG Dong, SHI Zhong-Ke

2011, 11(2): 44-51.

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As a pivotal component of intelligent transportation system, intelligent vehicles aim to reduce traffic accidents and improve transportation system efficiency, eventually, accomplish the objective of assisting or totally replacing drivers to control vehicles. In this paper, a research is conducted on path planning and vehicle control for vision-based navigation intelligent vehicles under semi-structured road condition. Firstly, local inverse perspective transformation is introduced to transfer vision imaging system of intelligent vehicle, which contains infinite vision field, into real world coordinates system; then depth-first search method is used to calculate all accessible paths in current road environment. The travel route, meanwhile, is preset under constraint of collision-free; after that, the travel time and vision image information are taken as inputs of a hierarchical fuzzy controller which is designed for vehicle control; finally, field test in real-road environment demonstrates the system not only satisfies all the design functions, including obstacle avoiding, path planning and vehicle autonomous driving, but also achieves a high effectiveness and stability.

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Pedestrian Simulation in Transportation Hub Based on NOMAD Model

ZHANG Rui, YANG Jing, HAN Dong, LEI Xi-Wen

2011, 11(2): 52-57.

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After the characteristics analysis of pedestrian in transportation hub, the social-force based NOMAD model is found to be very suitable for micro-simulation of pedestrian behavior and evaluation of pedestrian facilities. In addition, the hierarchical structure, input conditions and model building ideas of the NOMAD model is proposed. Furthermore, some important parameters are calibrated based on traffic survey data, then the Fuxingmen transfer station is simulated by the model. Based on the simulation results, characteristics of this station are analyzed and some quantization parameters that associate with the transfer system are obtained. By comparing simulation data and observational data, NOMAD model is found to be well adopted to the simulation of pedestrian transfer behavioral characteristics in the transfer hub. The relative error between simulation and observational data is less than 10%. It verifies the validity of applying NOMAD model for pedestrian simulation in transportation hub.

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Technology Development Envelope Approach for the Adoption of Future Powertrain Technologies: A Case Study on Ford Otosan Roadmapping Model

DAIM Tugrul, GERDSRI Nathasit, KOCKAN Irmak, KOCAOGLU Dundar

2011, 11(2): 58-69.

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Industry, government, and academia have started to adopt the technology roadmapping concept to setup their technology strategy, identify gaps and opportunities in their R&D activities. Automotive industry, facing fierce competition with continuous technological breakthroughs and improvements, should have roadmaps with respect to their company objectives that have flexible features so that organizations can reassess and adjust their roadmaps in a timely manner according to the impacts of the changes. This study focuses on future powertrain systems with the aim of defining the most probable implementation roadmap for the different alternatives to improve powertrain efficiency.

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The Robust Model of Continuous Transportation Network Design Problem with Demand Uncertainty

SUN Hua, GAO Zi-You, LONG Jian-Cheng

2011, 11(2): 70-76.

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In the urban traffic network, the trip generations of every origin and trip attractions of every destination are closely related to the economic level of the traffic zone, land-use, population and the other factors, generally can be accurately forecasted, while the demands between the origin and the destination are difficult to accurately predict. In this paper, we assume that the trip generation of every origin and trip attraction of every destination is deterministic, but the demands between every origin and destination are uncertain and belong to a bounded interval. We propose a min-max model of continuous network design with demand uncertainty under user equilibrium with robust optimizations. For our proposed model, we apply sensitivity analysis combined with the methods of sequence average algorithm to solve the robust model. Numerical examples demonstrate that the robust solutions of the continuous network design are more reliable than the deterministic solutions.

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Evaluation Method about Bus Scheduling Based on Discrete Hopfield Neural Network

LIU Zhi-Qiang, ZHANG Li, LV Xue , CHEN Jie

2011, 11(2): 77-83.

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According to characteristics of the evaluation about optimization of bus scheduling, this paper puts forward an evaluation method based on the Discrete Hopfield Neural Network (DHNN). At the course of constructing DHNN, the authors have selected the effective time-use law, average transfer time, transport capacity match and operating profit as evaluation indicators about the bus scheduling, according to running efficiency, smooth convergence, coordination capacity and company running profit. These indicators are independent of each other and quantifiable. At last we design the DHNN programming with MATLAB, and make this method be able to evaluate the bus scheduling conveniently and reasonably; thus it has a broader applicable scope. Finally, the method is verified by an example, and the calculation has been compared with the Delphi, the traditional evaluation method. Results show that the method is reasonable and effective. Compared with Delphi, this method is simple and easy to promote and has superiority to other methods.

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Node Importance Evaluation Method for Highway Network of Urban Agglomeration

SONG Xin-Sheng, WANG Xiao-Xiao, LI Ai-Zeng, ZHANG Lei

2011, 11(2): 84-90.

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Urban agglomeration is a strong vitality subsystem of large regional city system with significant regional advantages in space and linked features in network. Objective and accurate assessment of each node importance of highway network is a vital part for regional road network layout planning. Problems in the existing node important evaluation methods are analyzed. And for the characteristics of urban agglomeration, urban flow intensity is included into node importance assessment indexes system. Factor analysis is used as an objective method to avoid random subjective values in node importance calculation. K-Means clustering method is used to distinguish degree level of each node importance for further analysis. Finally, central china city agglomeration is taken as an application example, and the result shows the method proposed in this paper has good practical value in application.

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Capacity Analysis of Signalized Intersections under Mixed Traffic Conditions

LIANG Xiao, LIU Zhi-Li, QIAN Kun

2011, 11(2): 91-99.

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This paper presents a new approach for calculating straight lane capacity under mixed traffic conditions, especially in China. The First Discharge Headway (FDH) is applied as a novel to improve stop line method model, and the influencing factors of FDH are analyzed. To calibrate the FDH probability distribution, investigation data of four intersections in Beijing are employed. The Equivalent First Discharge Headway (EFDH) is proposed to replace the current empirical value in traffic capacity calculation. Using the improved model, the paper analyzes conflicting pedestrian and non-motor volumes’ impact on capacity under mixed traffic conditions. The results show that FDH is only related to vehicle type and external disturbance factors (α<0.05), and there is no mutual influence between each other. The Weibull distribution could well be applied to describe the probability distribution of the FDH. Though the EFDH correction, the calculation error of capacity is reduced to less than 5%. The traffic capacity presents exponential decline with the increase of conflict frequency between pedestrians, non-motors and motorized vehicles, the conflict influence is diminishing marginal utility.

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Side Constrained Traffic Assignment Model Based on Network Dual Equilibrium

HE Sheng-Xue, HE Jian-Jia, XU Fu-Yuan

2011, 11(2): 100-105.

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One side constrained traffic assignment model is presented based on local nearsighted user equilibrium principle by taking advantage of network dual equilibrium theorem. The traffic flow and travel time are regarded as a pair of dual variables. The analysis is started from the basic elements of network. At first, the dual relationships between the conservation conditions of node’s flow and the shortest travel time from origin to the node are considered. Then the dual relationships between link flow and travel time constrains on link with nearsighted users are also analyzed. At last, through combining these dual relationships and adding generalized side constraints, new traffic assignment model is built. How to embody two behavioral assumptions (priority of playing cards and elasticity of route adjusting on route) in the proposed algorithm to the model is analyzed. A searching method of effective path set is given by using the model’s solution results of unique link flow with respect to origin and destination pair. Several numeral examples are given to prove the validity and efficiency of the model and related algorithm. The results for the side constrained model are explained by congestion pricing and queuing delay on links.

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Multi-objective Optimization Method of Signal Timing for the Non-motorized Transport at Intersection

CHEN Xiao-Hong, QIAN Da-Lin, SHI Dong-Hua

2011, 11(2): 106-111.

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Considering the coordination between vehicle and non-motorized, different traffic composition have different signal control operates at the urban road intersection. In view of the multi-objective property of urban traffic signal control, the paper presents a multi-objective signal timing optimization model with vehicle volume and the non-motorized transport number as the inputs and traveler delay, stops and traffic capacity as the optimization objectives, and saturation degree is taken as restrictions. Furthermore, the method can adjust the weight of performance indexes according to mixed traffic composition. The multi-objective model is solved by genetic algorithm. The result shows that the model can give better signal timing than Webster method on the trade-off among various objectives and improve the traffic congestion effectively under mixed traffic condition.

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Optimal Integration of Macro Network for Urban Transit System

ZHAO Hang, AN Shi, HE Shi-Wei

2011, 11(2): 112-118.

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The problem of optimal integration of macro network for urban transit is studied by mixed integer optimization. The optimal design modal is formulated by level of service between zones, transit capacity and travel demands. The multi-objective modal synthetically considers the optimization of transit construction cost, hubs construction cost and unit operation cost, which includes the cost of passengers total travel time, the investment cost, the energy cost and pollution cost, and computational approach of schemes is provided. The efficiency of solution is improved by branch-cut algorithm. The feasibility and effectiveness of the modal and the algorithm is testified by the experimental example, and it is showed that the optimal plan schemes for different development phases are discovered by the algorithm to meet requirement for different level of service. The results indicate that the model and solution should be a promising way to improve the macro network of urban transit.

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Signal Priority Model for Buses and Other Priority Vehicles

LI Da-Ming, ZHAO Xin-Liang, SUN Qi

2011, 11(2): 119-123.

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Nowadays, traffic congestion is getting more and more serious in big cities. Public transportation system is an effective solution to this problem. Thus, bus signal priority control is very important to improve the efficiency and service level of public transportation. This paper proposes a novel city main road bus signal priority model, analyzes and demonstrates its impact. According to this model, we simulate the mode of transit signal priority and obtain satisfactory results. First, we use “single path of travel distribution method” to calculate OD matrix on the basis of the collected traffic flow data. Second, we use the GIS information to reconstruct the network in the micro-traffic emulational software “Paramics”. Third, we introduce the Analytic Hierarchy Process（AHP）to set the priority factors of four different vehicles according to traffic management strategy. Finally, we design a special control strategy to reduce the overall delay of buses. Simulation results show that after using the priority signal control programs, the delay of buses and other road priority vehicles, even that of all the vehicles has reduced as a whole. The results confirm that the application of priority signal control program can partially solve the access problems of buses and other vehicles which have the road priority.

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Bus Frequency Optimization Model Based on Using Synthetic Evaluation

YAO Bao-Zhen, YANG Cheng-Yong, SHEN Fei, YU Bin

2011, 11(2): 124-129.

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Bus frequency optimization is a major component of transit operation. In this paper, an optimal model for bus frequency of a bus line is developed, which aims to minimize the total cost of passengers and bus operators. The model can give attention to the benefits of both the bus operators and the passengers. To determine the weights of the cost for bus operators and passengers, a synthetic evaluation method is used to calibrate the model by using the data from Dalian city. A heuristic algorithm-shuffled complex evolution method (SCE-UA) is also adopted to solve the model. Finally, the model and the algorithms are tested on bus line 23 and 406 of Dalian city. The results show that the proposed model can effectively weigh the cost for bus operators and passengers, and improve the operation efficiency. The results also suggest that the algorithm has a good performance to deal with the problem.

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Evaluation of Connection Model of Intercity Railway and Suburban Rail Transit Based on Rough-Set

ZONG Chuan-Ling, YANG Chong-Ming, YANG De-Ming

2011, 11(2): 130-135.

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Urban space layout moves to establish the structure of network, equalization and multi-kernel with the fast enhancement of urbanization. The barriers and differences in regions will gradually disappear and integrate as a whole fully. To make transfer between urban rail and metro achieving the effect of “tight space, time compact”, this paper using the method of determining weighting coefficient based on rough set theory and through calculating the weighting coefficient of the grey clustering model to evaluate the transfer model between the urban rail and metro, in the same time this paper also explains the feasibility of this method with actual cases.

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Estimation Model for Operating Costs of Urban Rail Transit Based on Fuzzy Clustering

CHEN Jin-Jie, WANG Xing-Ju, GAO Gui-Feng

2011, 11(2): 136-141.

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The paper proposes an estimation model for operating costs of urban rail transit based on fuzzy clustering, which is applied to calculate life cycle costs of urban rail transit. We take Shijiazhuang urban rail transit Line 1 as an example, and select 14 feature attributes which are per capita GDP, total length, length of laying mode, ratio of laying mode, total quantity of the station, quantity of station for building method, ratio of station for building method, quantity of vehicles, workload of operating, average station distance and so on. Moreover, we take 23 urban rail transit lines as the sample data to estimate operating costs. We divide operating costs of the sample data into high operating costs and low operating costs to calculate the operating costs of ground line and underground line respectively. The estimation results show that underground line operating costs of urban rail transit are about two times greater than ground line operating costs.

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Method of the Carrying Capacity during Rush Hour on Intercity Railway

QU Si-Yuan, XU Xing-Fang, ZHANG Yi

2011, 11(2): 142-148.

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The carrying capacity during rush hour on intercity rail is an important technical parameter to ensure good traffic organization, and determining its value is with a certain complexity and uncertainty. According to actual operating features during rush hour on intercity railway in China, based on making use of the existed calculating methods, and by analyzing influence factors, the time of train interval and overtaking between different class trains, the paper adopts the improved mode of negative index distribution, and advances the calculated method of carrying capacity during the rush hour on intercity railway. The method has been strived to practicality, availability, convenience, accuracy. The paper gives an example of certain division on Hu-Ning intercity highway railway, which is being constructed on the foundation of train graph in the future to explain the new method. The result indicates that the method accords with the actual situation on intercity railway. The use of the method will be for reference on calculating carrying capacity on passenger dedicated railway.

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Methods of Calculating the Maximum Assembling on Urban Rail Transit Platforms

ZHAO Yu-Gang, MAO Bao-Hua, YANG Yuan-Zhou, HE Tao

2011, 11(2): 149-154.

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The changing of passenger flow is analyzed and simplified on urban rail transit platforms by stages. A method of calculating the maximum assembling on urban rail transit platforms with invariable train headway is given, under the circumstance that passengers get off the train before others get on. Further, after analyzing the distribution of train headways under the circumstance that deviations of train headways exist during train operations, a modified method of calculating the maximum assembling on platforms with deviations of train headways according to specified probabilities is given. In a case of an urban rail transit station, the maximum assembling on the island-platform of this station with deviations of train headways is calculated by methods before-mentioned. The maximum assembling on platforms obtained by calculate methods of this paper are smaller, compare with the calculate method given by current code for design of metro.

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Mixed Traffic Flow Cellular Automaton Model Based on Shared-Use Sidewalk

DENG Jian-Hua

2011, 11(2): 155-159.

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Study on the pedestrian-bicycle mixed traffic on the shared-use sidewalks beside to the street, with developing a multi-scale and multi-neighborhood-rule cellular automaton model. The shared-use sidewalk is a novel mode of non-motorized traffic management, but there is lack of theoretical support to select the plan and design parameters, lack of a quantitative method to evaluate the traffic flow state of shared-use sidewalks. The study’s object is the synclastic mixed pedestrian and bicycle traffic on a single shared-use sidewalk of urban street. A unified mixed traffic flow cellular automaton model is established based on the difference of the geometric dimensions, status value and neighborhood definition of bicycle-cell and pedestrian-cell. This model describes nicely the interference of bike and pedestrian. It is convenient to obtain evaluation parameters of traffic flow status like as hindrance probability, to provide a reliable theoretical basis as planning and designing the shared-use sidewalk.

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Design of Pedestrian Twice Crossing Street and Impact to Pedestrian Delay

LI Ang, SHEN Ming

2011, 11(2): 160-165.

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Pedestrian is an important part of the mixed traffic flow. How to solve the interference between the pedestrian flow and the vehicle flow is the important element to improve the status of China’s urban transport. In this paper, the pedestrian twice crossing the street program and its research on pedestrian delay are intended to solve the intersection of pedestrian and vehicle traffic interference and conflict. The dissertation comprehensive analyses pedestrian crossing facilities. Summed up the conditions and design the standards to set the pedestrian twice crossing the street settings, analyse the change of different signals and the pedestrian delay model. Simulate the different cases of Sitongqiao intersection. The pedestrian twice crossing the street can improve the safety of pedestrians, save the waiting time, increase the efficiency of pedestrians, reduce the rate of illegal pedestrians cross the street and reduce interference between vehicles.

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Convergence Analysis of ILC Based Ramp Metering under Constraints

ZHAO Ming, HOU Zhong-Sheng, YAN Jing-Wen

2011, 11(2): 166-173.

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In actual freeway traffic system, the on-ramp flow and the mainline speed are constrained. Therefore, it is necessary to take these constraints into consideration in controlling the freeway traffic flow. ILC based freeway ramp metering has become a research hotspot these years, however, there is no corresponding convergence analysis under input and state constraints. In this paper, the traffic density control problem is first formulated into an output tracking problem. Next, with rigorous analysis, the ILC based freeway ramp metering is able to guarantee the asymptotic convergence of the traffic density to the desired one, despite the presence of velocity and input constraints. The control performance under constraints is further verified by intensive simulations.

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Prediction of Urban Expressway Travel Time Based on SVM

ZHANG Juan, SUN Jian

2011, 11(2): 174-179.

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With the development of the Urban Expressway Traffic Information Collection System, in particular, the development of video license plate capture system, it is possible to access real-time dynamic expressway travel time, and at the same time, the demand of theoretical research and practical applications of high accuracy travel time prediction is raised. Based on mass of historical time series data detected by license plate recognition system on expressway, four periods of data before forecast period are selected as the input features. In order to achieve dynamic travel time prediction, support vector regression machine is adopted, and model parameters optimization algorithm is created, then trained model is gotten. Finally, three typical sections from Shanghai expressway systems are chosen and the SVM model is used. Compared with the traditional exponential smoothing method, the multiple regression method and the ARIMA method, the mean abs. percent error of SVM model is under 5% and Theil inequality coefficient is very close to 0. It can be seen that the SVM model in this article shows higher prediction accuracy.

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Module Structure of traffic mode Choice in Guangzhou

JIN An, ZHOU Zhi-Hua, LIU Ming-Min

2011, 11(2): 180-186.

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This paper focuses on module structure of traffic mode choice in terms of model framework, basic form of utility function, and parameter calibration and validation, based on resident trip survey in Guangzhou. The basic principle of mode split is proposed, and hierarchical division through non-car family, car family, and motorcycle family. This basic hierarchy partition is illustrated using an example of car family. Next, the method and basic steps of parameter calibration and key points of parameter validation are presented. In the final section, the forecasting results and field data are compared for validation purposes. The use of these household attributes increases the accuracy of the model, while the introduction of income, car ownership, and travel volume characteristics improve the adaptability of the model. The results will provide guidance for structure of traffic mode choice in similar-type cities.

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Characteristics of Driving Behavior and Traffic Accident in Automated Enforcement

JIANG Xian-Cai, ZHAO Zi-Qin, HUANG Ke

2011, 11(2): 187-192.

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In China, there is no enough research on the characteristics of driving behavior and traffic flow in automated enforcement, so that it is difficult to formulate the operations of traffic safety effectively. The paper analyzes the changes in driving characteristics, speed characteristics and traffic safety characteristics before and after automated enforcement by the methods of traffic investigation and data analysis. The result shows that traffic offenses of automated enforcement are reduced indeed, but the pedestrian accidents are added and the severity of traffic accidents is aggravated. The proportion of traffic violation of commercial vehicles is increased, the main offenders are younger drivers. There is serious risk of traffic accident at the end of the green time in signalized intersection. Besides, the automated enforcement couldn’t control the problem of exceeding speed at highway. So, this research proposes many measures (such as adding propaganda and education before carrying out the automated enforcement, and formulating the safety operations during the process of automated enforcement running) to ensure the running safety in automated enforcement.

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